大管径大流量抽采系统与高位钻孔综合治理上隅角瓦斯应用实践

Application practice of large diameter and large flow extraction system and high position drilling comprehensive treatment of upper corner gas

工作面回采期间顶板周期性破断,上覆岩层裂隙发育程度不断增加,形成气体运移通道,上邻近层瓦斯通过裂隙通道汇集在上隅角区域,形成瓦斯积聚区,增加瓦斯爆炸风险。针对此,提出在山脚树矿221015工作面采用大管径、大流量结合高位钻孔治理上隅角瓦斯超限难题。结果表明,上隅角瓦斯浓度由2.0%~3.0%降至0.5%以下,回风瓦斯浓度由0.8%降至0.5%以下,高位钻场浓度增幅达到30%左右,月推采进度由60 m提高到120 m,瓦斯日发电量由5.6万kWh增加到8.6万kWh,高位钻孔瓦斯抽采纯流量增加到1.4 m^(3)/min左右,在现场应用中取得了良好的技术与经济效益。

During the mining of the working face,the roof breaks periodically,and the degree of crack development in the overlying rock layer continues to increase,forming gas migration channels.The gas in the upper adjacent layers gathers in the upper corner area through the crack channels,forming a gas accumulation area,which increases the risk of gas explosion.In order to solve the above problems,it was proposed to use large pipe diameter and high flow combined with high-level drilling to control the problem of gas exceeding the limit in the upper corner of No.221015 working face of Shanjiaoshu Mine.The results showed that the gas concentration in the upper corner dropped from 2.0%~3.0%to below 0.5%,the gas concentration in the return air dropped from 0.8%to below 0.5%,the concentration of the high drilling site increased by about 30%,and the monthly mining progress increased from 60 m up to 120 m,the gas power generation has increased from 56,000 kWh/d to 86,000 kWh/d,and the net flow rate of gas drainage in high-level boreholes has increased to about 1.4 m^(3)/min.Good technical and economic benefits have been achieved in field applications.